• Title/Summary/Keyword: Ultraviolet radiation

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In Vitro Mechanistic Studies of Photogenotoxicity of Polycyclic Aromatic Hydrocarbons

  • Park, Jong-Hoon
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2003.10b
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    • pp.106-106
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    • 2003
  • Many polycyclic aromatic hydrocarbons (PAH) are acutely toxic to fish and other aquatic organisms in the presence of environmentally realistic intensities of solar ultraviolet radiation (SUVR). The phototoxicity of polycyclic aromatic hydrocarbons (PAHs) occurs through photodynamic activation of PAH compounds. Oxygen molecules react as quenchers with excited triplet states of PAHs producing reactive oxygen species (ROS).(omitted)

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Effects of supplementary UV-B radiation on growth and protein biosyntheses in rice (Oryza sativa L.)

  • Takeuchi, Atsuko;Hidema, Jun;Kumagai, Tadashi
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.332-334
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    • 2002
  • We examined the effects of supplementary ultraviolet-B (UV-B) radiation on the changes in synthesis and degradation of ribulose-I, 5-biphosphate carboxylase /oxygenase (Rubisco) and light-harvesting chlorophyll a/b binding protein of PSII (LHCII), as well as mRNA levels for small and large subunits of Rubisco (rbcS and rbcL, respectively) and LHCII (cab) with leaf age in UV-sensitive rice (Norin I) and UV-resistant rice (Sasanishiki). Both Rubisco and LHCII were actively synthesized until the leaf had fully expanded, and then decreased with leaf age. Synthesis of Rubisco, but not LHCII, was significantly suppressed by UV-B in Norin 1. The degradation of Rubisco was enhanced by UV-B around the time of the leaf maturation in the two cultivars. The levels of rbcS and rbcL were reduced by UV-B at the early leaf stages after emergence in both cultivars. The level of cab was first present at the highest level in the two cultivars, but drastically decreased due to UV-B treatment immediately after leaf emergence in Norin 1. It was proved that synthesis and degradation of Rubisco and LHCII greatly changed with leaf age: Rubisco synthesis was significantly suppressed by supplementary UV-B radiation at the transcription step during the early leaf stages. It was also suggested that the difference between the two rice cultivars in sensitivity to UV-B in the synthesis of Rubisco might be due to the specific suppression not only after transcription but also at transcription.

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The Measurement and Analysis for Ultraviolet Radiation (자외선복사의 측정과 분석)

  • Han, Jong-Sung;Kim, Hong-Bum;Kim, Hoon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.19 no.2
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    • pp.7-12
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    • 2005
  • When a light is projected upon a material, part of its radiant energy is absorbed and the rest is reflected or transmitted according to the nature of the material. The molecules of the substance absorbing a light obtains the radiant energy to make thermal reactions or photochemical reactions. Specially, photochemical reactions by ultraviolet(UV) radiation brings about photochemical degradation such as color change. Because the photochemical damage brings about a devaluation of material and once damaged, it is irretrievable, it is necessary to minimize the damage and conserve the native quality of a material by a protective lighting system. This paper presents the measurement and photochemical damage for UV radiation from light sources. We measured the optical radiations from artificial light sources and daylight, and we analyzed a functional relation between irradiance and UV radiation form the results.

IoT Enabled Intelligent System for Radiation Monitoring and Warning Approach using Machine Learning

  • Muhammad Saifullah ;Imran Sarwar Bajwa;Muhammad Ibrahim;Mutyyba Asgher
    • International Journal of Computer Science & Network Security
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    • v.23 no.5
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    • pp.135-147
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    • 2023
  • Internet of things has revolutionaries every field of life due to the use of artificial intelligence within Machine Learning. It is successfully being used for the study of Radiation monitoring, prediction of Ultraviolet and Electromagnetic rays. However, there is no particular system available that can monitor and detect waves. Therefore, the present study designed in which IOT enables intelligence system based on machine learning was developed for the prediction of the radiation and their effects of human beings. Moreover, a sensor based system was installed in order to detect harmful radiation present in the environment and this system has the ability to alert the humans within the range of danger zone with a buzz, so that humans can move to a safer place. Along with this automatic sensor system; a self-created dataset was also created in which sensor values were recorded. Furthermore, in order to study the outcomes of the effect of these rays researchers used Support Vector Machine, Gaussian Naïve Bayes, Decision Trees, Extra Trees, Bagging Classifier, Random Forests, Logistic Regression and Adaptive Boosting Classifier were used. To sum up the whole discussion it is stated the results give high accuracy and prove that the proposed system is reliable and accurate for the detection and monitoring of waves. Furthermore, for the prediction of outcome, Adaptive Boosting Classifier has shown the best accuracy of 81.77% as compared with other classifiers.

Photoimmunological and Photobiological Action of Infrared Radiation

  • Danno, Kiichiro
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.194-196
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    • 2002
  • While ultraviolet radiation alters various cutaneous cell functions, little is known about photo-immunological and photobiological effects of infrared radiation (IR) on the skin except its local thermal effects. The fIrst part of this study demonstrated that single exposure of mouse skin to near IR (0.7 - 1.3 $\mu$m) reversibly suppressed the proliferating activity of the epidermis, the density of Langerhans cells, and the ability of skin to induce contact hypersensitivity reaction. The second part demonstrated that the rate of wound closure was significantly accelerated by repeated exposures in animal models. The production of transforming growth factor-$\beta$l and matrix metalloproteinase-2, which are responsible for the wound healing processes, was significantly upregulated by irradiation, as shown by enzyme immunoassay, zymography, and reverse transcription polymerase chain reaction. Thermal controls were negative. The results suggest that near-IR irradiation can modulate the epidermal proliferation and part of the skin immune system, and stimulate the wound healing processes, presumably by non-thermal effects.

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Preparation of Solid Polymer Electrolytes by Ultraviolet Radiation and the Electrochemical Properties of Activated Carbon Supercapacitor Adopting Them (자외선 조사에 의한 고체 고분자 전해질의 제조와 이를 채용한 활성탄 수퍼커패시터의 전기화학적 특성)

  • Won, Jung Ha;Kim, Yong Joo;Lee, Young-Gi;Kim, Kwang Man;Kim, Jong Huy;Ko, Jang Myoun
    • Journal of the Korean Electrochemical Society
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    • v.16 no.2
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    • pp.91-97
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    • 2013
  • Solid polymer electrolyte films are prepared by ultraviolet radiation in the mixtures of an ionic liquid salt (1-ethyl-3-methylimidazolium tetrafluoroborate, $EMIBF_4$) and solvent (acetonitrile (ACN) or propylene carbonate(PC)), and an oligomer (poly(ethylene glycol)diacrylate, PEGDA, 45-60 wt.%). Electrochemical properties of activated carbon supercapacitors adopting the solid polymer electrolyte films as a separator are also examined by cyclic voltammetry and impedance measurement techniques. As a result, the supercapacitor adopting the PEGDA as much as 45 wt.% exhibits a superior capacitance of $46Fg^{-1}$ at $20mVs^{-1}$. It seems that this is due to fast kinetics of ion conduction by sufficient film flexibility, which can be allowed by comparatively weak ultraviolet curing of small anount of the PEGDA.